Roller cutter and antifriction bearing assembly for earth boring drills



c. E. REED 2,076,000

FOR EARTH BORING DRILLS April 6, 1937.

AN ANTIFRICTION BEARING ASSEMBLY Original Filed Aug. 6, 1935 Q'Za7;ence EReed,

EMW A Patented Apr. 6, 1937 UNlTED STATES PATENT- OFFICE ROLLER CUTTER BORING DRILLS AND ANTIFRICTION BEARING ASSEMBLY FOR L EARTH Application August 6, 1935, Serial No. 34,991

Renewed December 15, 1936 2 Claims. (Cl. 255-71) The invention concerns a form of roller cutter,

spindle, and anti-friction bearing assembly for 1o friction bearings,

earth boring drills intended to provide a simple and efilcient construction, andone adapted for boring wells of comparatively small diameter, although the invention is not limited in this respect.

In the accompanying drawing Figure 1 is a side view of the spindle, antiand the spindle support with the roller cutter shown in section assembled therewith.

Fig. 2 is a side view of the spindle and its support with the anti-friction bearings and cutter omitted.

In this drawing, l indicates the body portion of the spindle which is of frusto-conical form, Integrally formed with the smaller diameter end of this body is a flange 2 which provides the terminal free end of the spindle. This flange has a beveled face 5 adjacent the frusto-conical body portion, and its terminal face t is beveled and provides a friction bearing surface to take the end thrust of the rotary toothed cutter 5. The beveled face 3 of the terminal flange 2 is adapted to receive contact from the end faces 6 at the smaller ends of the frusto-conical rollers i. These rollers find a bearing surface on the frustoconical body portion i. The base faces of these frusto-conical rollers'at the larger ends thereof find a bearing against the face of the undercut side face 9 of an enlarged annular portion or shoulder of the spindle structure, indicated at 9. The peripheral surface of this enlarged portion ii is cylindrical. This portion is of larger diameter than the larger diameter end at the base of the irusto-conical body portion i. its undercut face 3 overliesthe end face at the large end of the frustoconicalroller for about one-half of its diameter. The said annular portion 9 is connected with the support it which extends at an angle to the axis of the spindle and is adapted to be secured in any desirable manner to the bit head. This support is made up of a main body portion Mia. and the shank portion liib. The portion 9 is integral with the body portion Ida, and this is true also of all parts of the spindle the body portion llia, the annular shoulder portion ii, the body portion i of the spindle, and its and the connected support. In other words, the support i@ with the shank idb,

which, while sustaining the roller cutter in place, will allow it to have free rotary movement. Cooperating with the frusto-conical rollers for this rotative locking efiect upon the rotary cutter, there is employed a ring 6 l having a screw threaded connection at E2 with the roller cutter within the base portion thereof. This ring finds a seat at it on a shoulder of the cutter. The ring bears upon the larger end faces of the frustoconical roller bearings for about one-half the diameter of said faces, and the inner circumference or bore oi the ring surrounds the peripheral surface of the annular portion 9 of the spindle construction.

End thrust outwardly from the'vertical axis of the bit head, which is indicated diagrammatically by the line X-X, is taken by the beveled terminal face d at the free end of the spindle, and, in part, this end thrust is also taken by the conical rollers, and the shoulder 8, formed by the undercut wall of the portion 9. Any tendency of the roller to slip off from the spindle and anti-friction rollerassembly in a direction towards the vertical axis of the drill will be resisted by the ring I I bearing upon thelarger end faces of the frusto-conical rollers.

. In assembling the parts of ring H, which is formed in one piece, is passed over the flange 2 of the spindle and also over the annular portion 9 so as to surround the peripheral face of said portion. It may be noted that the annularportion is of larger diameter than the flange 2, and the inner hereof the ring H is of a diameter which will enable it, as just stated, to slipped into place surrounding said portion 9.

the appliance, the

This ring is exposed beyond the lower end of the g is turned into connection with the screw threaded I part of said ring.

. The ring may be secured to the cutter in any suitable manner, as by welding at it. The ring ii may be held against turning while the cutter is attached thereto by any suitable form of wrench engaging recesses formed in the ring, or it may be otherwise held.

I claim:

1. A roller cutter, spindle and anti-friction bearing assembly for earth boring drills, comprising'a spindle having a frusto-conical bearing 5 portion with an annular flange at its smaller diameter free end, and with an annular shoulder at its larger diameter end], frusto-conical roller bearings on said body portion having their smaller end faces engaging said annular flange, and

10 their larger diameter end faces in part engaging the annular shoulder on the spindle, a frustoconical roller cutter mounted on the frusto-conical roller bearings and having a ring shaped member held within its base and bearing on a part 15 of the larger diameter end faces of the frustoconical bearing rollers, said rollers taking end thrusts of the frusto-conical roller cutters both outwardly and inwardly in respect to the vertical axis 01' the drill, the outward end thrust being imposed upon the peripheries of said rollers, and sustained by said shoulder and the inward thrust being imposed upon the larger diameter end faces of said rollers, and transmitted through said rollers to the annular flange.

2. A roller cutter spindle and anti-friction 

